This invention concerns ratcheting wrenches which apply torque to a hexagon bolt or nut or other screw fastener in one work direction and release from the nut or bolt in the opposite direction, without having to remove the tool from the nut or bolt.
In a number of situations, a conventional ratcheting socket wrench cannot be used. In some situations such a wrench may not be available. An open-end wrench, on the other hand, can be slipped over a hexagon-shaped fastener from the side, not only from the top as in a socket a wrench. However, using an open-end wrench is inconvenient in a situation where it is not possible to turn the wrench and nut or bolt in large arcs of movement. The open-end wrench has to be repeatedly removed from the nut or bolt and re-inserted, the small arc of rotational movement made, and then the process repeated, sometimes many times. This resetting of the tool for each fraction of a turn is very time-consuming. Some adjustable wrenches tend to become stuck on the nut if the adjustment screw is set tightly, causing further difficulty.
For such situations it is desirable to have an open-end wrench with a rachet feature, allowing application of torque to a hexagon bolt or nut in one work direction, while allowing slippage in the opposite rotational direction.
Several forms of ratcheting open-end wrenches are known. For examples, see U.S. Pat. Nos. 4,488,459, 5,095,782, 5,941,142, and 5,960,679. Some of the ratcheting open-end wrenches of these patents are adjustable to accommodate different sizes of fasteners.
In the invention described herein, ratcheting wrenches that ratcheted open-end wrenches, both adjustable and non-adjustable have unique and efficient mechanisms providing the ratcheting. In the preferred form of adjustable wrench, the ratcheting feature allows the movable jaw of the wrench to retract away from the fixed jaw when the handle is rotated in one direction, such that the wrench slips over the facets of a polygon-shaped nut. In the opposite direction or work direction, the ratcheting mechanism locks the jaws in position so that they cannot spread. A jaw adjustment screw, similar to that of a conventional open-end adjustable wrench, is positioned for rotation in the wrench head to adjust the lower jaw position, and is axially movable along with the lower jaw, but only when a support wedge is slidingly retracted out from its normal position supporting the bottom end of adjustment screw. Rotation of the wrench handle in the non-work direction, i.e. rotation away from the lower jaw, is effective to retract this support wrench and thus to allow retracting movement of the lower jaw to open the wrench. The wrench handle is pivotally connected to the wrench head, which includes the fixed upper jaw. When the wrench handle is pulled in the non-work direction, the handle pivots relative to the head, and a linkage member pivotally secured to the handle at a position back from the head pivot point of poles and retracts the support wedge, which progressively lowers the support level for the adjustment screw and lower jaw. The lower jaw and adjustment screw preferably are spring-biased toward the jaw-open position, and as the wrench is further rotated in the non-work direction, the jaw opens and the wrench slips to the next nut facet position, whereupon the jaws close again to the original position and the wrench handle returns to normal alignment with the wrench head, under the influence of another spring which urges the wrench toward the normal position.
In one particular embodiment, the wrench includes a slidable fence device on the fixed jaw, to be moved slidably over a face of the nut or bolt head when the wrench is in place, providing a stop against sliding of the wrench off the nut or bolt head.
Another optional feature is a locking device to prevent the wedge from retracting, when is not desired. For example, the tool may be needed in a tight place where the tool can only be used in one orientation that would otherwise result in ratcheting.
In another embodiment, the adjustment screw is eliminated and the jaw is simply moved into engagement with a nut via a slide button. In this embodiment a pair of matching racks of teeth are included between the movable jaw and the fixed head, each notch in the racks of teeth representing an incremental nut size for spacing between the jaws.
In one embodiment of a non-adjustable open-ended wrench, the wrench again has a fixed jaw, but this fixed jaw is rigidly secured to the wrench""s handle. A movable jaw coacts with the fixed jaw such that both sides of a nut can be engaged. This movable jaw has a base end pivoted to the wrench handle, but such that the pivoted movable jaw can slide outwardly, spreading away from the fixed jaw as it slides. The pivot includes a slot so that pivot point itself can slide. A wedge at the end of the movable jaw slides along a jaw stabilizer which is formed in a fixed position as part of the handle. When the wrench is rotated in a non-work direction, i.e. away from the movable jaw, the movable jaw slides outwardly in being pulled by the corners of the polygon-shaped nut against the pressure of a spring which urges the movable jaw toward its normal position. Thus, the nut corners pull the movable jaw outwardly and allow it to slip over the facet and the corner of the nut, until a position is reached in which the two jaws are parallel to the next pair of opposed nut facets. At this point the movable jaw is forced by the spring back toward the handle. If the wrench is then rotated in the opposite direction, i.e. a work direction, in a rotational direction wherein the handle is moved toward the movable jaw, the movable jaw then becomes locked in position and the movement of the handle rotates the nut along with the wrench. The movable jaw stays in place, with its pivot axis at the bottom of the slot in the handle.
The wrenches described above increase the speed and convenience of removing or tightening a bolt or nut whenever a conventional ratcheting socket wrench cannot be used. The wrench can be slipped over any square or hexagon shape from the side, not only from the top. The adjustable ratcheting wrench replaces a set with many different sizes of wrenches and thus makes much more convenient some types of work in tight places, such as under a car where it is difficult and inconvenient to retrieve various sizes of wrenches for different fasteners. The adjustable wrench can be made in different sizes for different ranges of nut sizes, and also the handle can be made in different lengths, which can be substituted by removal of a few pins or pivot shafts. The handle can be foldable if desired, for better access in tight work places.
These and other objects, advantages and features of the invention will be apparent from the following description of a preferred embodiment, considered along with the accompanying drawings.